In Minnesota, state health officials are studying two chemicals widely used in frac-sand processing as contaminants of “emerging concern.”

Four years into a mining boom that is reshaping parts of the rural countryside, mining companies and government regulators are coming to grips with the reality that the new industry involves much more than scooping sand out of the ground and hauling it away.

The states’ burgeoning frac-sand industry, they have found, creates waste streams they are scrambling to understand and control.

From pyramids of discarded sand to sludge that accumulates in filtering devices, the mines create tons of waste byproducts that must be managed until they can be plowed back into the ground as part of reclamation plans designed to protect the environment and preserve the rural landscape.

“The industry just came on too fast,” said Ruth King, a stormwater specialist with the Wisconsin Department of Natural Resources. “I wish we could turn back the clock a couple of years and start over.”

In a rash of continuing violations that started last year, heavy rains have combined with sand-processing water to overflow holding ponds on several mining sites. The breaches have dumped sandy sediment into public waters, where it can suffocate fish eggs, kill aquatic plants and rob fish of habitat they need to reproduce.

“It really does impact the fisheries side of it,” said Roberta Walls, another Wisconsin DNR water specialist.

Rich Budinger, president of the Wisconsin Industrial Sand Association, an industry trade group, said sediment pollution is indeed a threat to natural areas. The entrance of new, inexperienced sand companies and heavy rains have made conditions more challenging, he said. But, he noted, the state requires frac-sand companies to obtain stormwater permits, which should be sufficient to prevent lasting environmental damage. Any habitual violator should not expect to stay in business, he said.

“It shouldn’t be an ongoing issue,” Budinger said. “This doesn’t represent the industry as a whole.”

20 violations

Heading into this spring, the Wisconsin DNR had cited 15 frac-sand mines for alleged violations of water regulations, including two that advanced to the Wisconsin Department of Justice for possible legal sanctions. Since then, Walls has written at least four new violation notices and King is handling another.

“It’s very challenging,” Walls said. “I really don’t see the state being able to provide the staffing levels that the workload demands.”

Most large frac-sand mines, she said, are properly sized and engineered, with zero discharge to neighboring streams and wetlands. Problems have cropped up at smaller sites where man-made holding ponds are barely large enough to contain water used for processing sand — much less heavy spring rains, melting snow and water that drains from wet stockpiles.

The Great Northern Sand processing site near New Auburn, Wis., is a case in point. Last November, the site spilled sediment-filled wastewater into Beaver Creek, which leads to an important wildlife sanctuary in Barron County, according to state records.

Jim Drost, a former U.S. Bureau of Mines engineer and an expert in industrial sand, said he was angered by the spill because he and others had warned that the site would produce sediment pollution.

Drost grew up in the area and fears that silt from a cluster of surrounding frac-sand operations will wipe out local habitat for such rare creatures as the Karner blue butterfly and Butler’s garter snake.